Oxytocin: Anti-insulin-like effects in isolated fat cells

doi:10.1016/0003-9861(84)90344-8

Archives of Biochemistry and Biophysics

Volume 234, Issue 1, October 1984, Pages 230-234

https://doi.org/10.1016/0003-9861(84)90344-8 Get rights and content

Abstract

Oxytocin has both insulin-like and insulin antagonistic actions in fat cells in vitro. The anti-insulin-like effects of oxytocin in dispersed rat fat cells have been studied. The magnitude of the anti-insulin-like activity varies with the metabolic pathway of glucose utilization; oxidation [¹⁴CO₂ production], 32%; glycogen synthesis (d-[U-¹⁴C] glucose incorporation into glycogen), 77%. In addition, direct inhibition of the activation of fat cell glycogen synthase has been shown. These inhibitory effects depend upon an intact disulfide ring, since the ability of N-ethylmaleimide-reacted oxytocin to inhibit insulin-stimulated processes was reduced by more than 90% when compared to the intact molecule.

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Oxytocin: Anti-insulin-like effects in isolated fat cells

Abstract

J. Biol. Chem

J. Biol. Chem

J. Biol. Chem

Biochim. Biophys. Acta

FEBS Lett

Anal. Biochem

Endocrinology

Endocrinology

Eur. J. Biochem